In a medium bowl, mix together veal, beef, breadcrumbs, parsley, garlic, salt, oregano, and pepper. Scoop into 18 heaping tablespoons, and roll each scoop between the palms of your hands to form a compact ball. Heat olive oil in a large sauté pan over medium-high heat. Brown meatballs until golden, about 10 to 12 minutes; place on a plate. Pour grease from pan and discard, and return meatballs to the pan. Add marinara, and simmer over medium-low heat until meatballs are cooked through and tender, about 15 to 20 minutes. Divide meatballs and sauce among 4 plates and serve warm.